4-12 Loss-of-Potential, Load Encroachment, and Directional Element Logic Date Code 20001006
SEL-351 Instruction Manual
Figure 4.6: Internal Enables (32VE and 32IE) Logic for Zero-Sequence Voltage-Polarized
and Channel IN Current-Polarized Directional Elements
Note 1: If channel IN is rated 0.05 A nominal, then setting option “I” is not available for setting
ORDER. This results in internal enable 32IE defaulting to logical 0 at the bottom of
Figure 4.6. The channel IN current-polarized directional element that follows in
Figure 4.10 is defeated and nonoperational when internal enable 32IE = logical 0.
Thus, the channel IN current-polarized directional element in Figure 4.10 is defeated,
nonoperational, and unavailable when channel IN is rated 0.05 A nominal.
Note 2: If the voltage inputs are delta-connected, then setting option “V” is not available for
setting ORDER. This results in internal enable 32VE defaulting to logical 0 (see middle
of Figure 4.6). The zero-sequence voltage-polarized directional element that follows in
Figure 4.9 is defeated and nonoperational when internal enable 32VE = logical 0.
Courtesy of NationalSwitchgear.com
To Next Page
Loading...
